Multifunctional portable computing device with special housing

ABSTRACT

A portable computing device includes pivoting and hinging mechanisms which enable its housing to reconfigure to function in multiple modes. In one configuration the device functions as a laptop computer with keyboard input. In another configuration the device folds into a compact, hand-held, pen-based computer. In another configuration the device folds around the display for protection during transport. A set of adjustable stops enable easy and repeatable transitions between the different configurations.

BACKGROUND—FIELD OF INVENTION

The invention relates to portable computers and specifically to portablecomputers with housings that can be reconfigured to perform multipletasks.

BACKGROUND—PRIOR ART

The miniaturization of electronic devices, and particularly portabledevices, has generated the need for a keyboard which can collapse to thecompact size of the portable device. The keyboard must also expand fromthe compact state to an extended state which is large enough toaccomodate the fingers of human hands. A mechanism is needed to providefor a smooth and reliable collapse and extension of the keyboard. Themechanism should also maintain alignment of the components and shouldnot interfere with the typing.

The miniaturization of electronic devices, and in particular theirevolution into portable devices, has generated the need for method toprotect and store the display during transport. The display should bemovable to several positions so that a display of compact size can givea wide range of functionality to the portable device.

In collapsible computing devices, the display typically pivots from aclosed position to an adjustable open position. Each time the device isopened, the user needs to manually readjust the display to the desiredviewing angle. Other pivoting components may need a similarlyreproducible adjustment. The requirement to read-just each pivot eachtime the device is opened compromises the convenience of the device andlimits the number of pivoting components that can be used in a practicaldevice. Thus, there is a need for a pivoting mechanism that canreproduce a desired angle without the need for manual adjustment.

Portable computing devices are generally supported on table surfaceswhich are significantly below the eye level of the user. The displaysize of such devices is limited by a desire for compactness. There is aneed for a mechanism to raise the display of these portable computingdevice closer to the eyes of the user to provide greater readability.

Each of the various portable computing devices available can meetspecific needs. Laptop computers provide the full functionality of akeyboard, pointing device, and large display screen. However, they aregenerally very bulky and heavy. Very compact handheld computing deviceslack the functionality of a laptop computers.

To get the full range of uses of a computing device, a user must useseveral devices. This requires redundant investment in the hardware,software, and training. It also requires additional maintenance of thehardware, software, and battery charge.

Thus, there is a need for a design which can combine manyfunctionalities into a single device.

OBJECTS AND ADVANTAGES

It is an object of the invention to provide:

-   a) an ergonomic keyboard with a hinging mechanism which does not    interfere with typing, yet lets the keyboard collapse into a more    compact form;-   b) a keyboard hinging mechanism which is simple, reliable, and    inexpensive;-   c) a keyboard hinging mechanism which maintains alignment of the    keyboard sections during the collapse of the keyboard, and rigidly    connects the keyboard sections in the fully collapsed condition;-   d) a keyboard hinging arrangement which facilitates the routing of    wires between the keyboard sections;-   e) a keyboard hinging mechanism which allows the keyboard sections    to open to a split configuration, with a greater spacing at the    front for more natural positioning of the hands.

It is a further object of the invention to:

-   a) allow a display to share the footprint of a folded keyboard;-   b) allow the display to move to and from a protected position for    transport;-   c) allow the display to move to an adjustable, inclined position    leaving a keyboard accessible for typing;-   d) allow the display to move to flat position alongside the housing    for pen input;-   e) allow the display to move to an inclined position in which the    device is suitably stable for pen input;-   f) allow the display to be positioned in the front of the device so    that the housing can be hidden from view;-   g) provide cushioning to protect the display;-   h) eliminate the need to readjust the display angle each time the    computer is opened;-   i) minimize the force required to move the display between the open    and closed positions;-   j) reduce the difficulty and number of steps required to open and    close the computer;-   k) provide a device which can open using only pivoting movements;-   l) provide a stable configuration of the device in which the display    is extended toward the user for enhanced readability.

It is a further object of the invention to provide a combinedmultifunctional portable computing device for which:

-   a) the user need invest in only a single device, so that the expense    of redundant electronic devices is avoided;-   b) a charge need be maintained only on a single set of batteries;-   c) the bulk of carrying several devices is avoided;-   d) the expense of buying several sets of software is avoided;-   e) the labor in installing multiple sets of software and maintaining    several operating systems is avoided;-   f) the expense and labor in translation between incompatible sets of    software is avoided;-   g) the training for several different devices and input paradigms is    avoided.

SUMMARY

Keyboard

According to the invention, the keyboard is divided into two sections.In the open, extended position the sections are arranged side by side sothat a standard arrangement of keys such as the “QWERTY” arrangement canbe accomodated.

In one embodiment the keyboard sections abutt directly against oneanother in the open position such that the keytop surface is continuous.

In another embodiment, the front portion of the keyboard sections areseparated in the open position. This spacing orients the keyboardsections at an outward angle. This angle reduces the flexing of thewrists and gives a more natural and comfortable typing position.

One of the keyboard sections is pivotally supported to swing about anaxis located above the plane forming the keytop surface. To collapse,this section swings 180 degrees so that the keytop surfaces are inface-to-face relationship. A display may be stored between these keytopsurfaces in this collapsed condition. This display may have a size andaspect ratio similar to that of each of the keyboard sections.

In some embodiments of the invention, a combination of two differenttypes of pivotal connections connect the two keyboard sections.Connected to the rear portions of the keyboard sections are two lugswhich extend above the keytop surfaces and are connected by a singleaxle. This axle defines a single axis of rotation. This axle may behollow to facilitate the routing of wires. In contrast, the frontportions of the keyboard sections are connected through a link whichretracts below the keytop surface in the open position. At each end ofthe link a lug connects the link through an axle to a corresponding lugattached to each keyboard section. An alignment pin secures the keyboardsections in the closed position.

Display

The display hinging mechanism enables the display to move betweenseveral positions. It enables a single portable device to performseveral functions.

A double-acting hinge connects the display to a keyboard base. The firstpart of the hinge pivots the display from a storage position face-downon the top of one keyboard section to a typing position at an angleinclined above the keyboard. The second part of the double acting hingeallows the display to pivot further around to lay on the reverse surfaceof the keyboard section. In this position the display is accessible forpen input.

A prop can position the display at an angle above the reverse surface ofthe keyboard section. The prop completes the third segment of atriangular configuration formed with the display and the keyboardsection.

In this propped configuration, the heavy components incorporated intothe keyboard housing form a stable base. The display faces outward andupward from the triangular configuration, so that is fully visible andhides the prop and base from view. Forces applied onto the display bypen input are directed to a point on the base, so that the device isvery stable against tipping when forces from pen are applied to apropped display.

This transition of the display from the storage position to the laptopposition to the propped position to the flat pen input position iseffected only through hinging motion about two axes of a simpledouble-acting hinge. This movement is easily effected and does notrequire any complex translations or combinations of sliding and rotatingmotions.

An adjustable stop can be used in conjunction with the pivots toreproduce a previous pivot angle without the need for manual adjustment.

Link Mechanisms

A portable computing device uses a pair of link mechanisms to raise itsdisplay toward the user for better readability. The link mechanisms cancollapse from an open, extended configuration to be stored within thecollapsed computing device. The heavy components of the device areincorporated into the keyboard components so that the center of gravityof the device is very low. This provides a stable base from which thedisplay can be supported. A set of adjustable stops enable the displayto be reproducibly raised to the desired viewing position. The closerviewing position allows a smaller, pocket-sized display to fulfill thefunction of a larger laptop display with a smaller area andcorrespondingly lower power consumption.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1A shows a first embodiment of the keyboard in an open, extendedposition.

FIG. 1B shows the first embodiment of the keyboard in the collapsedcondition.

FIG. 2 is an exploded view of the first pivot mechanism in the firstembodiment.

FIG. 3 is an exploded view of an alternate first pivot mechanism in thefirst embodiment.

FIG. 4 shows a second embodiment of the keyboard in an open position inwhich the front of the keyboard sections are spaced from each other.

FIG. 5 shows the second embodiment of the keyboard in a collapsedcondition.

FIG. 6 shows a shroud covering the front portion of the secondembodiment of the keyboard in the collapsed condition.

FIG. 7 shows a shroud pivoting to cover the end portions of the secondembodiment of the keyboard in the collapsed condition.

FIG. 8 shows a shroud when the keyboard is in the extended position.

FIG. 9 shows the display in the protected position between the foldedkeyboard sections.

FIG. 10 shows an end view of the configuration of FIG. 9.

FIG. 11 shows the device in a partially open position in which thekeyboard is in the extended position.

FIG. 12 shows an end view of the configuration of FIG. 11.

FIG. 13 shows the device fully opened to a position suitable forkeyboard input.

FIG. 14 shows an end view of the configuration of FIG. 13.

FIG. 15 shows the display in a position on top of the folded keyboard,with the display surface exposed for pen input.

FIG. 16 shows an end view of the configuration of FIG. 15.

FIG. 17 shows the device with the display in a propped position on topof the folded keyboard.

FIG. 18 shows an end view of the configuration of FIG. 17.

FIG. 19 shows a front view of the configuration of FIG. 17.

FIG. 20 shows an end view of the device in a transport configuration.The prop protrudes outward from the device to function as a handle.

FIG. 21 details a pivot mechanism with a spring-loaded stop and areleasable catch for a double-acting display hinge.

FIG. 22 shows a display of a compact computing device supported by twolink mechanisms.

FIG. 23 shows the compact computing device with the link mechanisms inthe collapsed condition.

FIG. 24 (not to scale) details a horizontally stacked link mechanism.The thickness is exaggerated to show detail.

FIG. 25 is a top view of a vertically stacked link mechanism.

FIG. 26 is a side view of a vertically stacked link mechanism.

FIG. 27 shows the cushioning of the display support and the display.

DESCRIPTION OF THE SPLIT KEYBOARD SHOWN IN FIGS. 1–3

FIG. 1A shows a keyboard 110 split into two keyboard sections, a rightkeyboard section 112 and a left keyboard section 114. These keyboardsections fold to the collapsed condition shown in FIG. 1B.

A split keyboard and display was disclosed in the co-pending commonlyowned U.S. patent application Ser. No. 08/515,383, filed Aug. 15, 1995,which was a continuation of U.S. patent application Ser. No. 08/202,333,filed Feb. 24, 1994. The title was “A Collapsible Keyboard and DisplayMechanism for a Computer System”. These parents of the presentapplication are expressly incorporated in full here by reference.

The xyz coordinate system is fixed with respect to keyboard section 112.The x-y plane is parallel to a bottom surface 127 of keyboard section112. The x-axis coincides with the rotation axis of the first pivotmechanism 115. X is zero at the rear end of the first pivot mechanism115.

A first pivot mechanism 115 is detailed in the exploded view of FIG. 2.Lugs 116 and 117 and are attached to keyboard section 112 proximate toits rear portion 120. Lug 118 is attached to keyboard section 114proximate to its rear portion 122. A journal bearings 124 lines lug 118.An axle 125 connects the lugs. Thus, the lugs and journal bearings actas axle bearing members. The first pivot mechanism restricts thepivoting of keyboard section 114 with respect to section 112 torotations about the x-axis shown in FIG. 2.

An alternate configuration 115 b of a first pivot mechanism is shown inthe exploded view of FIG. 3. Lug 126 has thrust bearing surfaces 128 and130. These surfaces mate with thrust bearing surfaces 132 and 134 oflugs 136 and 138, respectively. An axle 140 pivotally connects the lugs.This alternate first pivot mechanism restricts the pivoting of keyboardsections 114 with respect to section 112 to rotations about the x-axisshown in FIG. 3.

Both pivot mechanisms 115 and 115 b align the rotation of the keyboardcomponents about the x-axis and resist rotations about the y- andz-axes. Pivot mechanism 115 incorporates a journal bearing 124 of anextended length to provide a moment arm against torques in the y- andz-axes. Pivot mechanism 115 b incorporates thrust bearings 126, 128,132, and 134 of an extended diameter to provide a moment arm againsttorques in the y- and z-axes.

As shown in FIG. 1A, plurality of touch responsive keys 142 protrudefrom top surfaces 144 and 146 of respective keyboard sections 112 and114. The tops of (undepressed) keys 142 define keytop surfaces 148 and150, which are approximately planar and parallel to respective topsurfaces 144 and 146. Keys 142 are movable to a depressed position.Depressed keytop surfaces 152 and 154 correspond to the plane defined bythe tops of keys 142 in a depressed position. Depressed keytop surfaces152 and 154 lie approximately 3 mm below keytop surfaces 148 and 150,respectively.

The rotation axes of first pivot mechanisms 115 and 115 b can be locatedon keytop surfaces 148 and 150. For embodiments in which a display isstored in a space between keyboard sections 112 and 114 in the collapsedcondition, the rotation axes of pivot mechanisms 115 and 115 b arelocated above the keytop surfaces 148 and 150.

A second pivot mechanism 160 connects the keyboard sections 112 and 114proximate to their respective front portions 156 and 158. This pivotmechanism 160 may be hidden from view behind the space bar. A link 162is pivotally attached to lugs 164 and 166 through axles 168 and 170. Inthe open condition, the link 160 retracts beneath the keytop surfaces148 and 150.

When the keyboard 110 is in the open position, the top inner surfaces162 and 164 of the subset of keys 142 which are adjacent to the abuttingsurfaces are spaced from one another. This spacing prevents interferencebetween the surfaces 162 and 164 during the pivoting about axles 168,170, and 125 while collapsing the keyboard. During collapse, the frontportion pivots through an arc whose radius is one-half the distancebetween the centers of axles 168 and 170. In some configurations, thesubset of keys 142 adjacent to the abutting surface may depress oneanother during the collapse to achieve clearance.

In the collapsed condition of FIG. 1B an alignment pin 169 in keyboardsection 114 mates with a cavity 171 in keyboard section 112. Alignmentpin 169 in combination with first pivot mechanism 115 secure keyboardsections 112 and 114 against relative sliding in the x-y plane.Furthermore, alignment pin 169 is spaced a distance from the first pivotmechanism 115 to provide a moment arm to resist torques about the z-axisand prevent relative rotations about the z-axis.

In the collapsed condition of FIG. 1B, a display may be protectedbetween the keyboard sections 112 and 114. When keyboard sections 112and 114 are exposed to shock or bending, the display may remaincushioned and isolated from the shock and in a planar condition by thekeys 142 being selectively depressed by the display. The display is freeto move in the region between the depressed keytop surfaces 152 and 154.

The spacing of the keyboard components 112 and 114 is maintained in thecollapsed condition by pivot mechanisms 115 and 160 and by pin 169.Thus, the spacing of the planar keyboard sections is maintained at threepoints. Furthermore, these three points are distributed at distant endsof the planar keyboard, so that each portion of the keyboard sections iswell supported. This rigid structure is capable of protecting a displaystored between the collapsed keyboard sections 112 and 114.

This configuration results in a keyboard which can collapse to a rigidstructure, which has a pivot mechanism 115 in the rear which canmaintain a well-defined pivot axis during collapse, and which has apivot mechanism 160 in the front portion which retracts so as not tointerfere with typing.

This combination of features was achieved using pivots in which onlyrotational movement is required. These rotational pivots have severaladvantages over sliding members. The rotational pivots are simple andsturdy. Their bearings are easily sealed to retain lubrication and toprevent debris from entering and interfering with their operation. Thesliding motion within pivoting components is proportional to the axlediameter, and their total sliding distance is usually less than than thetranslational motion of sliding members. This results in less frictionalenergy consumed for easier and smoother movements. Their axle diametercan be reduced to further reduce the frictional torque and to givesmoother operation. The combination of the axle's cylindrical journalbearing surfaces and circular thrust bearing surfaces restrict themotion to a single rotational degree of freedom and are very stiffagainst other movements. Wires may be routed through a hollow axle forprotection and to guide them through a well-defined torsional flexure.

Description of the Keyboard and Shroud Shown in FIGS. 4–8

FIG. 4 shows an alternate embodiment of the keyboard 110 in the openposition. The front portion of the inward facing surfaces 172 and 174are spaced from each other. As a result, the keyboard sections 112 and114 are oriented at a relative angle. This “natural” position may reducethe required flexure of the user's wrists and provide him with a morecomfortable typing position.

In this embodiment the inward facing surfaces 172 and 174 do not abuttagainst one another and may be smooth surfaces. In the closed positionshown in FIG. 5, the lugs 164 and 166 may protrude from keyboardsections 112 and 114.

When the keyboard 110 is in the open position, its front portions 156and 158 lie below the keytop surfaces 148 and 150 to allow the user'shands to access the keys 142. As shown in FIG. 5, this results in a gapbetween front portions 156 and 158 in the closed position.

To cover this gap, a shroud 176 is attached through pivot mechanisms 178and 180 to the bottom of front portion 156. The shroud 176 is shown inFIGS. 4 and 5; first in an extended position in which its bottom surfaceis coplanar with the bottom surface 127 of the keyboard section 112. Theshroud 176 can pivot to a second position shown in FIG. 6 in which itcovers the front portions 156 and 158 as well as the intervening gap.The shroud 176 is positioned in the keyboard front, so that a displaywhich may be connected to the rear of the keyboard can pivot to a peninput position without the need to move the shroud 176.

A touch-sensitive surface 182 is attached to the shroud 176. When theshroud is in the second position (see FIG. 6), this surface is protectedfrom damage. When the shroud 176 is in the first, extended position, thetouch sensitive surface 182 is accessible to the user's thumbs. Thistouch sensitive surface supplements the keyboard input with tracking andpointing information.

FIG. 7 shows a rear view of the keyboard 110 in the collapsed condition.Upon collapse of the keyboard 110, a spring 184 rotates a second shroud186 about a pair of coaxial pivots 188 and 190 to cover the surfaces 172and 174.

FIG. 8 shows a rear view of the keyboard 110 on the open position. Ashroud 192 is similar to shroud 186 in dimensions and configuration inthe opened and closed positions. The shroud 192 differs in that itemploys a grooved engagement system rather than a spring closuremechanism. A section 192 a of shroud 192 is attached to keyboard section112 through pivots 188 and 190. A section 192 b of shroud 192 ispivotally attached to section 192 a and is slidably engaged to keyboardsection 114 through pin 194 and groove 196.

Overhanging surfaces 198 and 199 of keyboard sections 112 and 114,respectively, mate with shroud 186 in the closed position. In the openposition, surface 198 and 199 are adjacent.

In the embodiments of FIGS. 7 and 8, the locations of shrouds 186 and192 are constrained only by the furthest protrusion of irregularsurfaces 172 and 174. This distance is one-half a key width beyond theaxis of the keyboard pivot 115. This distance need not be as large asthe thickness of keyboard sections 112 and 114. This results in acollapsed keyboard of reduced length.

Description of the Keyboard and Display in FIGS. 9–20

FIGS. 9 and 10 show the display 410 in the protected position. Thekeyboard sections 112 and 114 protect the display 410. The display 410is movable between keyboard sections 112 and 114 to isolate the display410 from shock, impact, and bending of keyboard sections 112 and 114.

Double acting hinges 412 and 414 allow the display 410 to pivot withrespect to keyboard component 114. Hinge 412 has two axle pivot members.Pivot 416 is attached to the keyboard section 114. Pivot 418 is attachedto the display 410. Link 420 connects pivot 416 and 418. Similarly,hinge 414 has two axle pivot members. Pivot 422 is attached to thekeyboard section 114. Pivot 424 is attached to the display 114. Link 426connects pivot 422 and 424 sections

Further protection against shock may be provided by extendable links 420and 426. Extension and compression of these links allows the portion ofthe display adjacent to the hinges 412 and 414 to translate toward andaway from the keyboard section 112. Alternately, an elastomericconnection between the display 410 and the pivots 418 and 424 mayprovide this cushioning effect.

Pivoting keyboard section 114 through an angle of 180 degrees to theextended position results in the configuration shown in FIGS. 11 and 12.Throughout this first pivoting movement the display 410 remains in afixed, face-down position with respect to keyboard section 114.

In a second pivoting movement, the display is raised to theconfiguration shown in FIGS. 13 and 14 by pivoting pivots 418 and 424.The display angle may be adjusted by adjusting the pivoting angle ofpivots 418 and 424.

The double-acting hinges 412 and 414 allow the display 410 to furtherpivot with respect to the keyboard section 114. First, the displayfurther pivots about pivot 418 and 424, so that it extends horizontallyoutward, 180 degrees from its position in FIG. 11 and 12. Next, thesecond pair of pivots 416 and 422 rotate an additional 180 degrees sothat the display lies against the reverse surface 428 (opposite from thekeys) of keyboard section 114. The double-acting hinge allows this to beaccomplished in a single rotating movement, which simplifies the processof changing the device configuration. Finally, the keyboard sections arefolded so that the device is configured as in FIGS. 15 and 16.

FIGS. 17, 18, and 19 show a propped configuration. Prop 430 is pivotallyconnected to keyboard section 114. The display 410 rests against theprop 430. The propped angle of the display 410 may be adjusted byadjusting the location at which the prop 430 supports the display 410.

FIGS. 17, 18, and 19 show a very compact and stable triangularconfiguration of the device. Only simple pivoting joints are needed, andthey are not required to bear the large torques that would be needed toresist rotation of a cantilevered prop. Typically a cantilevered propmust be rotatable to various angles with respect to the device housing,and a mechanism is needed to adjust the angle and to maintain thedesired angle against torques arising from forces applied at the end ofthe arm.

There are several advantages to this configuration. The first isstability. The heavy components, including the batteries andelectronics, are located in a base formed by keyboard sections 112 and114. This base lies flat on the table. Only the bare display 410 need beelevated. This results in a stable configuration with very low center ofgravity. The display 410 is located directly above this heavystabilizing base. Furthermore, the forces imparted by a pen push bothdownward and backward on the tilted display 410. Because the display islocated above the front portion of the base, these forces are directedtoward the base, so that the device is further stabilized againsttipping. In contrast, the forces applied to the display located in therear of a standard notebook computer tend to tip it over backwards.

The second advantage to this configuration is accessibility. The display410 surface faces outward so that no other components block access forpen input. The display 410 is located close to the table surface onwhich the device rests. The display 410 can be accessible for pen inputby a hand resting on the table surface. This configuration also resultsin a very small footprint, so that it may sit unobtrusively on a desk,much as a clock or calendar may sit. In this configuration with acalendar program running, it may in fact function as a calendar,appointment book, and alarm clock. This configuration also results in avery small visual “footprint”; normally only the visual area of thedisplay 410 is seen by the user. This display 410 largely blocks fromview the other computer components and leaves the user's field of viewuncluttered.

The third advantage is simplicity. The main components, the display 410and the keyboard sections 112 and 114, are connected through a set ofsimple pivots. Only rotational movement of the pivots is needed; nosliding motion required. The prop 430 can be attached to the keyboardcomponent, so that the prop 430 need add the weight and volume to thedisplay 410.

The triangular configuration is very stable structurally. Each of thetriangle's three contact points needs to support forces but does notneed to support torques. The need for the very strong clutches orsplines to support a cantilevered prop is obviated.

A configuration suitable for transport is shown in FIG. 20. The prop 430can be moved to a position in which is protruded outward from thekeyboard section 114. A handle 432 pivots out from the prop 430 to aposition centered between keyboard sections 112 and 114. In thisposition, the device will hang vertically below the centered handle 432with the center of gravity of the assemble of keyboard sections 112 and114 directly beneath the handle 432.

Thus, this single, simple, compact device can assume several positions.It can fold to enclose and protect the display. It can open to a typingconfiguration similar to a laptop. Its keyboard can fold with thedisplay lying flat to accept pen input. It can open to a triangularconfiguration for a desktop display and pen input device.

Description of the Adjustable Stop of FIG. 21

A shaft 510 connects a first pivoting component to a second pivotingcomponent. In FIG. 20, these pivoting components are the double-actinghinge 412 and the display 410. The shaft 510 is rigidly attached to thehinge 412. The display 410 is free to rotate about the shaft 510. Anadjustable stop 516 frictionally engages the shaft 510. An arm 517protrudes from the adjustable stop. A knob 518 is rigidly attached tothe stop 516 and accessible for manually adjusting the angle of the stop516 with respect to the shaft 510.

A spring 520 is wrapped around the shaft 510 and engages the hinge 412and the display 410. The display 410 is held between the spring 520 andthe arm 517 at a specified viewing angle 522 with respect to ahorizontal. This viewing angle 522 can be increased by rotating the stop516 in a clockwise direction. This clockwise rotation of stop 516 can beeffected by rotating either the knob 518 or the display 410 in aclockwise direction. The viewing angle 522 can be decreased by rotatingthe knob 518 in a counter-clockwise direction. Thus, adjustment of theangle of the stop 516 relative to the shaft 510 corresponds to anadjustable and reproducible display angle 522.

This adjustment allows display 410 to freely pivot through angles lessthan or equal to the display angle 522. The torque imparted by thespring 520 to the display 410 may be slightly larger than the torqueimparted by gravity. This gravitational torque can be calculated as theweight of display 410, times the distance of the center of gravity ofthe display 410 to its axis of rotation, times the cosine of its anglewith respect to the horizontal. Through this counterbalancing oftorques, the spring-loaded display 410 can easily and automaticallyclose and open reproducibly to an angle 522 predetermined by the mostrecent adjustment of stop 516. Manual adjustment is needed only whenthis predetermined angle 522 is to be changed. This adjustable stop 516obviates the need for routine adjustment each time the display isopened. This makes the compact computing device more convenient to use.

Adjacent to the double-acting hinge 412 is a mechanism which restrictsthe movement of the double-acting hinge. A “C”-shaped catch 523 isattached to the display 410. A “U”-shaped bar 524 is attached to ahorizontal keyboard section (not shown). When angle 522 is less than 180degrees, the catch 523 is constrained to rotate around the bar 524. Thisoccurs when the display 410 is to be used in the typing configurationshown in FIG. 13 and 14.

When the angle 522 is increased to 180 degrees, the catch 523 isreleased from the bar 524, allowing the display 410 to pivot anadditional 180 degrees about pivot 416. This enables the display 410 topivot to the reverse surface 428 of the keyboard section 114. Thisposition (shown in FIGS. 15 and 16) allows pen input.

In this way, the double-acting hinge 420 acts as a single hinge in thetyping position, where the display angle 522 is less than 180 degrees.The stop 516 can be used to maintain a preset display angle 522 suitablefor typing. When the display angle 522 is increased to 180 degrees, thecatch 523 releases to allow the double-acting hinge 412 to swing aroundin a single, natural movement to the pen input position shown in FIGS.15 and 16.

Description of the Link Mechanisms of FIGS. 22–27

In FIG. 22, a pair of keyboard sections 112 and 114 form a base forsupporting a display 410. The more massive components of the portablecomputing device such as the batteries, disk, electronic components, andarmor are incorporated into the keyboard sections 112 and 114. A minimumof weight is incorporated into the display 410. This configurationensures that the center of gravity remains over the base for stability.When placed on a flat surface such as a table, this configurationremains stable against tipping even when the display is extended beyondthe base to a position closer to the user.

The display is connected through double-acting hinges 412 and 414 to adisplay support 610. Link mechanisms 612 and 614 connect the displaysupport 610 to the keyboard section 114.

The bottom of the first link mechanism 612 is attached to the rearportion of the keyboard section 114. A pivot 616 connects a first link620 to the keyboard section 114. A pin 624 at the end of a second link622 slides within a slot 626. Links 620 and 622 are pivotally attachedto each other and to a sequence of pair of links which, in turn, aresimilarly pivotally attached to each other. A top pair of links 628 and630 is attached to the display support 610. Link 630 is attached to apin 632 which slides within a slot 634. Link 628 is attached through apivot 636. An adjustable stop 638 determines an angle 640 of link 628with respect to the display support 610. This configuration of linkswithin link mechanism 612 maintains a parallel relationship betweencomponents within the link mechanism 612 and between the keyboardsection 114 and the display support 610. This ensures that the displaysupport 610 remains horizontal throughout the adjustment of the heightof the display 410.

The bottom of the second link mechanism 614 is attached to the endportion of the keyboard section 114. A first link 644 is attached to thekeyboard section 114 through a pivot 644. A second link is attached tothe first link 644 through a pivot 645. An adjustable stop 648determines a relative angle 650 between links 642 and 646. A sequence ofpairs of links attach link 642 and 646 to top link 652. Link 652 isattached to display support 610 through pivot 654.

FIG. 23 shows the device with the link mechanisms 612 and 614 in thecollapsed condition. In this condition, the display support 610 isstored in the rear portion of the keyboard section 114 behind thecollapsed link mechanism 612. The link mechanism 614 is stored in theend portion of the keyboard section 114. From this configuration, thedevice may be folded to any of the configurations shown in FIGS. 9through 20.

Link mechanism 612 is detailed in the top view shown in FIG. 24. Thethickness of the links is exaggerated to show detail. Each link is abeam member. The links are arranged in pairs consisting of a curved linksuch as link 622 and a crank-shaped link such as link 620. Thecrank-shaped link has two flat sections 660 and 662 connected by a pivotshaft 664 which passes through a circular hole at the center of thecurved link 622. The end of the crank-shaped link 620 is connectedthrough a pivot pin 666 to the end of the next curved link. The end ofthe curved link 622 is connected through a pivot pin 668 to the end ofthe next crank-shaped link. An arbitrary number of pairs of links can bestacked in this manner and can be stored in this flat horizontal storageposition.

Typical dimensions of the links are 1 mm thick×10 mm high×150 mm long.Typically, 4 pairs of links are used. The resultant dimension of themechanism in the horizontal storage position 12 mm thick×10 mm high×150mm long. This mechanism can extend to a maximum length of approximately500 mm. Thus, the collapsible mechanism can be stored within a foldedcompact computing device and extend to a length considerably greaterthan any dimension of the folded computing device.

The front end of link mechanism 612 is attached to the keyboard section114 (shown in FIG. 22). The far end of link 622 is connected to a pin624 which slides in a slot in the keyboard section 114. The far end oflink 620 is connected to a pin 624 which pivots in a hole in thekeyboard section 114.

The rear end of link mechanism 612 is attached to the display support610. The far end of link 628 is connected to a pin 636 which pivots in ahole in the display support 610. The far end of link 630 is connected toa pin 632 which slides in a slot 634 in the display support 610.

The portion of link 630 above its pivot 631 may be shorter than theportion of link 628 above its pivot 631. The portion of link 622 belowits pivot 621 may be shorter than the portion of link 620 below itspivot 621. This results in a tilting of link mechanism 612 in theextended position, and the centering of the display with respect to thekeyboard sections.

FIG. 25 shows a top view of link mechanism 614 in the storage position.The vertical stacking provides a path for routing wires 670 which carrypower and display signals from the keyboard section 114 to the display410.

FIG. 26 shows a side view of link mechanism 614 in the storage position.Link mechanism 614 is formed from a series of pairs of links such asouter link 642 and inner link 646. A pivot pin such as pin 645 connectsthe center of each outer link to its corresponding inner link. A pivotpin at each end of each outer link connect the outer link to an innerlink from an adjacent pair. Typically 5 pairs of links are used.

The bottom end of the link mechanism 614 is connected to front portionof the end of keyboard section 114 through pivot pin 644. The top end ofthe link mechanism 614 is connected to the display support 610 throughpin 654.

An adjustable stop 648 defines an adjustment angle of link 642 withrespect to link 646. A spring 672 acts to counterbalance the weight ofthe link mechanism 614 and the display 410.

Each link is approximately 10 mm wide×4 mm high×110 mm long. In thecollapsed condition the stack has dimensions of approximately 10 mm×20mm×110mm. In the extended condition link mechanism 614 is approximately500 mm long.

The horizontal stacking of mechanism 612 uses less space in the vertical(z) direction than the vertical stacking of mechanism 614. Thehorizontal stacking is therefore used in the rear hinge to minimize thevertical height of the collapsed link mechanism so that the display canfold over the link mechanism when the display is stored between thekeyboard sections in the collapsed condition. In the collapsed conditionspace is provided for movement of the display support in the verticaldirection (toward the keyboard sections) for additional cushioning ofthe display.

In some embodiments the link mechanisms are constructed of a metal, andthe wires are contained within recesses and passages within these metalcomponents. These passages may form a Faraday cage to shield the displaysignal from electro-magnetic interference (EMI). One of the metal linkmechanisms may also be used as an antenna for communications via acellular modem or wireless ethernet PC card.

In some embodiments the CPU, memory, mass storage, video drivers, andPCMCIA slots are incorporated into keyboard section 114. The batteriesare incorporated into keyboard section 112. With this arrangement onlythe power and the keyboard key switch signals need to cross the keyboarddivision. These signals are of low frequency and are not susceptible toEMI. The need for special sheilding of these wires is obviated.

Support and Rigidity of the Link Mechanisms

In discussing support and rigidity, a set of axes is chosen to coincidewith the corner of the display 410 as shown in FIG. 22. The x directionis oriented toward the user, the y is oriented toward the center of thekeyboard, and the z axis is oriented vertically upward.

The link mechanism must support the display in an extended positionagainst movement and vibration in an x, y, and z direction. It must alsosupport the display against rotation and rotational vibration about thex, y, and z axes.

The adjustable stop 638 maintains link mechanism 612 in a fixed length.This rigid mechanism maintains a fixed elevation of display againstmovement in the z-direction.

The location of the end of link 620 is fixed by pivot 616. The slot 626constrains movement of link 622 and prevents rotation of mechanism 612about the pivot 616. This combination prevents movement of the displayin the y-direction.

The adjustable stop 645 fixed the length of mechanism 614. This preventstilting of mechanism 612 in the x-direction and prevents movement of thedisplay in the x-direction.

The link mechanism 612 maintains a parallel relationship between the(stationary) keyboard sections and the and the display support. Thisprevents movement of the display about the x-axis.

Rotation of the display about the y-axis is associated with bending ofthe link mechanism 612. The stiffness of link mechanism 612 against thisbending mode is limited by the limited thickness (approximately 1 mm) ofthe links in mechanism 612. Further protection against rotation aboutthe y-axis may be realized by connecting the stop 638 directly betweenthe pivoting components consisting of the display 410 and the link 652.In this manner the considerable stiffness of link mechanism 614 againstrotation about the y-axis is employed.

Rotation of the display about the z-axis is constrained by linkmechanisms 612 and 614. Because the z-axis is oriented parallel to thegravitational force vector, there is little excitation of this mode andlittle tendency for rotation and rotational vibration about the z-axis.

Counterbalance springs may be incorporated into the adjustable stops 638and 648. Alternately, torque may be applied by springs incorporated intothe keyboard section 114.

Movement of the display in the x direction corresponds to movementcloser to the users eyes. This adjustment is effected by compression oflink mechanism 114. The pins 616 and 624 may allow a small amount ofrotation about the y-axis to allow link mechanism 612 to tilt forward inthe x direction toward the user.

Detailed Description of the Cushioning Shown IN FIG. 27

While the device is in the collapsed condition shown in FIG. 9, theconfiguration of the display 410, the keyboard sections 112 and 114, andthe link mechanisms 612 and 614 should allow movement of the display 410with respect to the keyboard members 112 and 114. This allows a stiff,brittle display 410 to remain planar even with bendable keyboardsections 112 and 114.

Further cushioning can be realized against impact by configuring thehinges 418 and 424 and link mechanisms 612 and 614 to allow translationin addition to rotation. In the closed position, sufficient clearance isallowed so that the link mechanisms 612 and 614 can move such that thedisplay 410 can move within the key travel region toward each keyboardsection 112 and 114.

Alternately, FIG. 27 shows an elastomeric mount 674 between the displaysupport 610 and the display 410. This elastomeric support may allowtranslation of the portion of the display proximate to the displaysupport 610 toward each keyboard section 112 and 114 when the device isin the collapsed condition. In addition, this elastomeric support mayprovide damping of vibrations of the display 410 relative to thekeyboard section 114. The damping of these vibrations is particularlyimportant when the link mechanisms 612 and 614 are in the extendedposition.

In FIG. 27 the display support 610 and elastomeric mount 674 extend tothe top portion of the display 410. In this collapsed configuration thedisplay support 610 acts as a shroud to cover the gap between frontportions of the keyboard components 112 and 114.

A feature of this design is cushioning distributed over the area of thedisplay 410. The resilience of the individual keys 142 shown in FIG. 1Acan act to apply a distributed force needed to accelerate/decelerate thedisplay 410 when the keyboard sections 112 and 114 areaccelerated/decelerated due to, for example, dropping the device. Thisminimizes the bending load applied to the display 410 due to impact.

In an optimal design the device has a closed position wherein there is aresting position in which the display 410 is normally spaced from thekeytop surfaces 148 and 150 to avoid routine and unnecessary scratchingand wear of the surfaces of the display 410. However, when bending,shock, or impact is imparted to the device, the display 410 (or portionsof the display 410) can cross over the keytop surfaces 148 and/or 150.When this happens, forces are applied to those portions of the display410 which cross over the keytop surfaces 148 and 150. This force tendsto cushion the display 410 and tends to accelerate the display 410 awayfrom the depressed keys 142 and back toward its resting position.

The keys on a standard keyboard are movable and have a restoring forceto provide tactile feedback as to whether the key has been depressed.This force is typically provided by an elastomeric member of the key.This force can be exploited as above to cushion the display.

This force of the key against the finger is a nonlinear function of keydisplacement. The force first increases with displacement up to athreshold, then decreases. Thus, once the threshold is passed, thelowered resisting force of the key tends to allow the key to move allthe way to the end of its travel. This is to provide the user with cleartactile feedback as to whether the key was pushed or not pushed.

When the key is also used for cushioning the display 410, the display410 can be protected from shocks of higher magnitude by modifying thenonlinear resilience of the key. The key can be allowed to move in ahyperextended range of key travel beyond the range of a normalkeystroke. The spring constant in this hyperextended travel range shouldbe significantly higher than that in the normal range of travel, so thatlarge forces can be applied for large impacts without the requirement ofcorrespondingly large additional key displacement in the hyperextendedrange.

This protection and cushioning of the display 410 reduces the need forthe protective armor typically surrounding laptop computer displays. Thedisplay 410 may be an unprotected glass panel, may have a thinnerprotection than a laptop, or may be protected only around its perimeter,such as by the display support 610 in FIG. 27.

The foregoing discussion should be understood as illustrative and shouldnot be considered to be limiting in any sense. While this invention hasbeen particularly shown and described with references to embodimentsthereof, it will be understood by those skilled in the art that variouschanges in form and details may be made therein without departing fromthe spirit and scope of the invention as defined by the claims.

1. A portable collapsible keyboard for input of data into a digitalelectronic device, said keyboard comprising: a) a first keyboard sectionhaving a top surface, a front surface and a rear surface, and a firstplurality of keys having keytops facing upward from said top surface,said first plurality of keys arranged substantially adjacent to oneanother to form a substantially contiguous first array of keys, saidkeytops of said first array of keys forming a substantially planar firstkeytop surface, b) a second keyboard section having a top surface, afront surface and a rear surface, and a second plurality of keys havingkeytops facing upward from said top surface, said second plurality ofkeys arranged substantially adjacent to one another to form asubstantially contiguous second array of keys, said keytops of saidsecond array of keys forming a substantially planar second keytopsurface, c) a rear pivot mechanism for pivoting said second keyboardsection with respect to said first keyboard section, said rear pivotmechanism connected to said first keyboard section adjacent to said rearsurface and having an axis of rotation fixed with respect to said firstkeyboard section, d) a front pivot mechanism for pivoting said secondkeyboard section with respect to said first keyboard section, said frontpivot mechanism connected to said first keyboard section adjacent tosaid front surface and having an axis of rotation fixed with respect tosaid first keyboard section, e) an elongate link of fixed length forspacing said first and said second keytop surfaces, said link pivotallyconnected at its first end to said front pivot mechanism, said linkconnected at its other end to said second keyboard section such that,when said keyboard is in an open configuration with said first andsecond keytop surfaces substantially parallel and facing the samedirection, the frontward portions of said first and said second keytopsurfaces are spaced apart from each other at least the length of thelink, and f) wherein said keyboard is collapsible through a pivotingaction from said open configuration to a closed configuration in whichsaid first and second keytop surfaces are in a face-to-facerelationship.
 2. The keyboard of claim 1 wherein said first and secondpivot mechanisms align any relative rotation of said second keyboardsection with respect to said first keyboard section about an x-axisfixed with respect to said first keyboard section and resist anyrelative rotation about all other axes.
 3. The keyboard of claim 2wherein said second keyboard section rotates 180 degrees about saidx-axis to collapse said keyboard from said open configuration to saidclosed configuration.
 4. The keyboard of claim 1, further comprising asubstantially planar display attached to said first keyboard section,said display having a front surface for display of information from amultifunctional portable digital electronic device.
 5. The keyboard ofclaim 1, wherein at least one of said front and said rear pivotmechanisms comprises a lug and axle.
 6. The keyboard of claim 5, whereinsaid lug and said axle comprise journal bearing surfaces and whereinsaid lug comprises a thrust bearing surface.
 7. The keyboard of claim 1,wherein said first and second pluralities of keys comprise substantiallyall of the keys from the respective right and left halves of a “QWERTY”keyboard.
 8. The keyboard of claim 1, wherein said first plurality ofkeys comprises a first space bar and said second plurality of keyscomprises a second space bar.
 9. The keyboard of claim 4, wherein: a)said first and second pivot mechanisms align any relative rotation ofsaid second keyboard section with respect to said first keyboard sectionabout an x-axis fixed with respect to said first keyboard section andresist any relative rotation about all other axes, b) said secondkeyboard section rotates 180 degrees to collapse said keyboard from saidopen configuration to said closed configuration, c) at least one of saidfront and said rear pivot mechanisms comprises a lug and axle, d) saidlug and said axle comprise journal bearing surfaces, e) said lugcomprises a thrust bearing surface, f) said first and second pluralitiesof keys respectively comprise keys from the right and left portions of a“QWERTY” keyboard, and g) said first plurality of keys comprises a firstspace bar and said second plurality of keys comprises a second spacebar.
 10. The keyboard of claim 1, said fixed length comprising at leastthree keytop widths.
 11. The keyboard of claim 1, said link connectedsuch that when said keyboard is in said open configuration, the frontportion of the inward facing surfaces of the keyboard sections arespaced from each other at least three keytop widths.
 12. Amultifunctional portable electronic device, comprising: a) A display, b)A collapsible keyboard attached to said display, comprising: i. a firstkeyboard section having a top surface, a front surface and a rearsurface, and a first plurality of keys having keytops facing upward fromsaid top surface, said first plurality of keys arranged substantiallyadjacent to one another to form a substantially contiguous first arrayof keys, said keytops of said first array of keys forming asubstantially planar first keytop surface, ii. a second keyboard sectionhaving a top surface, a front surface and a rear surface, and a secondplurality of keys having keytops facing upward from said top surface,said second plurality of keys arranged substantially adjacent to oneanother to form a substantially contiguous second array of keys, saidkeytops of said second array of keys forming a substantially planarsecond keytop surface, iii. a rear pivot mechanism for pivoting saidsecond keyboard section with respect to said first keyboard section,said rear pivot mechanism connected to said first keyboard sectionadjacent to said rear surface and having an axis of rotation fixed withrespect to said first keyboard section, iv. a front pivot mechanism forpivoting said second keyboard section with respect to said firstkeyboard section, said front pivot mechanism connected to said firstkeyboard section adjacent to said front surface and having an axis ofrotation fixed with respect to said first keyboard section, v. a link offixed length for spacing said first and said second keytop surfaces,said link pivotally connected at its first end to said front pivotmechanism, said link connected at its other end to said second keyboardsection such that, when said keyboard is in an open configuration withsaid first and second keytop surfaces substantially parallel and facingthe same direction, the frontward portions of said first and said secondkeytop surfaces are spaced apart from each other at least the length ofthe link, and wherein said keyboard is collapsible through a pivotingaction from said open configuration to a closed configuration in whichsaid first and second keytop surfaces are in a face-to-facerelationship.
 13. The device of claim 12, wherein said display ispivotally attached to said second keyboard section.
 14. The device ofclaim 12, wherein said display is attached to said first keyboardsection.
 15. The device of claim 12 wherein said first and second pivotmechanisms align any relative rotation of said second keyboard sectionwith respect to said first keyboard section about an x-axis fixed withrespect to said first keyboard section and resist any relative rotationabout all other axes.
 16. The device of claim 15 wherein said secondkeyboard section rotates 180 degrees about said x-axis to collapse saidkeyboard from said open configuration to said closed configuration. 17.The device of claim 12, wherein said display is substantially planar andhas a front surface for display of information from said device.
 18. Thedevice of claim 12, wherein at least one of said front and said rearpivot mechanisms comprises a lug and axle.
 19. The device of claim 16,wherein said lug and said axle comprise journal bearing surfaces andwherein said lug comprises a thrust bearing surface.
 20. The device ofclaim 12, wherein said first and second pluralities of keys comprisesubstantially all of the keys from the respective right and left halvesof a “QWERTY” keyboard.
 21. The keyboard of claim 12, wherein said firstplurality of keys comprises a first space bar and said second pluralityof keys comprises a second space bar.
 22. The device of claim 12, saidfixed length comprising at least three keytop widths.
 23. The device ofclaim 12, said link connected such that when said keyboard is in saidopen configuration, the front portion of the inward facing surfaces ofthe keyboard sections are spaced from each other at least three keytopwidths.